Experts say dangerous sleep apnoea affects an estimated 8 million in the UK alone, and everything from evolution to obesity or even the climate crisis could be to blame

When Matt Hillier was in his 20s, he went camping with a friend who was a nurse. In the morning she told him she had been shocked by the snoring coming from his tent. “She basically said, ‘For a 25-year-old non-smoker who’s quite skinny, you snore pretty loudly,’” says Hiller, now 32.

Perhaps because of the pervasive image of a “typical” sleep apnoea patient – older, and overweight – Hillier didn’t seek help. It wasn’t until he was 30 that he finally went to a doctor after waking up from a particularly big night of snoring with a racing heartbeat. Despite being young, active and a healthy weight, further investigation – including a night recording his snoring – revealed that he had moderate sleep apnoea. His was classed as supine, the most common form of the condition, meaning it happens when he sleeps on his back, and is likely caused by his throat muscles.